关于JAVA的小小的问题，望高手指点~

[A198905011]

Accomplish RandomCourse.java

[dracularking]

yes, it's a random problem.

obviously four courses they have the equal randomness.
every course has 25 percent opportunity of becoming the one ninety-ninth.

at last sum up the occurrences of them all, among 99 course objects, how many times does each appear?

generally it's a 25 percent random event.

[sniper4983]

创建类的时候就创建点标识符，比如都有一个相同的变量X，X取不同的值，然后做一个循环看有几个不同的X取值。
仅仅是个想法，LZ自己再想想吧。

[buzaibeishang4617016]

楼主不妨看看我这个程序：

import java.util.Random;
/**
 * @author 不再悲伤
 * Accomplish RandomCourse.java
 *You have 4 classes representing different courses: 
 *=Accounting,Economics, Finance, and Informatics.You 
 *need to creat RandomCourse class, then:
 *1. You randomly create n course objects (Here n = 99);
 *2. You output the exact numbers for different course 
 *objects.
 */
public class RandomCourse 
{
	public static void main(String[] args)
	{
		int Accounting=0,Accounting1=0;
		int Economics=1,Economics1=0;
		int Finance=2,Finance1=0;
		int Informatics=3,Informatics1=0;
		int[] b=new int[100];
		Random in=new Random(4);
		for(int i=0;i<100;i++)
		{b[i]=in.nextInt(3);}
		for(int i=0,j=i+1;i<100;i++)
		{
			if(b[j]==b[i]){Accounting1++;}
			if(b[j]==b[i]){Economics1++;}
			if(b[j]==b[i]){Finance1++;}
			if(b[j]==b[i]){Informatics1++;}
			j++;
		}
		System.out.println("Accounting"+Accounting1);
		System.out.println("Economics"+Economics1);
		System.out.println("Finance"+Finance1);
		System.out.println("Informatics"+Informatics1);
	}
}

[buzaibeishang4617016]

哦，楼主上面代码有问题，下面这个是对的

import java.util.Random;
/**
 * @author 不再悲伤
 * Accomplish RandomCourse.java
 *You have 4 classes representing different courses: 
 *=Accounting,Economics, Finance, and Informatics.You 
 *need to creat RandomCourse class, then:
 *1. You randomly create n course objects (Here n = 99);
 *2. You output the exact numbers for different course 
 *objects.
 */
public class RandomCourse 
{
	public static void main(String[] args)
	{
		int Accounting=0,Accounting1=0;
		int Economics=1,Economics1=0;
		int Finance=2,Finance1=0;
		int Informatics=3,Informatics1=0;
		int[] b=new int[100];
		Random in=new Random(4);
		for(int i=0;i<100;i++)
		{b[i]=in.nextInt(3);}
		for(int i=0;i<100;i++)
		{
			if(b[i]==0){Accounting1++;}
			if(b[i]==1){Economics1++;}
			if(b[i]==2){Finance1++;}
			if(b[i]==3){Informatics1++;}
		}
		System.out.println("Accounting"+Accounting1);
		System.out.println("Economics"+Economics1);
		System.out.println("Finance"+Finance1);
		System.out.println("Informatics"+Informatics1);
	}
}

[A_JSir]

针对从Shape衍生出来的所有东西，Shape建立了一个通用接口——也就是说，所有（几何）形状都可以描绘和删除。衍生类覆盖了这些定义，为每种特殊类型的几何形状都提供了独一无二的行为。
在主类Shapes里，包含了一个static方法，名为randShape()。它的作用是在每次调用它时为某个随机选择的Shape对象生成一个句柄。请注意上溯造型是在每个return语句里发生的。这个语句取得指向一个Circle，Square或者Triangle的句柄，并将其作为返回类型Shape发给方法。所以无论什么时候调用这个方法，就绝对没机会了解它的具体类型到底是什么，因为肯定会获得一个单纯的Shape句柄。

[livs_ly_2010]

我一直在郁闷，英语没学好，天天记单词到底有没有用。 但是我还是迷茫的记着。一天10+个。价值投资吧。